fossils
June 8, 2017

315,000-Year-Old Fossils Could Be Earliest Known Homo Sapiens

Newly discovered fossils belonging to “early... anatomically modern humans” discovered at a site in Morocco are 100,000 years older than the previously known Homo sapiens remains, new research published online earlier this week in the journal Nature have revealed.

According to the Washington Post, the earliest known Homo sapiens remains had dated back to approximately 200,000 years ago, but analysis of fossils found alongside stone tools at the Jebel Irhoud archaeological site have been dated to between 300,000 and 350,000 years old.

animation of  homo sapien fossil jawbone

Credit: Jean-Jacques Hublin, MPI-EVA Leipzig

The newfound bones feature a combination of primitive and modern traits, and indicate that by around 300,000 years ago, key changes to our species’ morphology had already taken place, lead researcher Jean-Jacques Hublin from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany and his colleagues reported in one of two papers published Wednesday.

While the Jebel Irhoud site was originally discovered back in the 1960s, the fossils described in the latest studies were found as part of a new expedition at the Moroccan location that started in 2004 and increased the number of fossils discovered there from six to 22, the authors noted.

Those fossils, which included skulls, teeth and long bones belonging to at least five individuals, were dated using a technique known as thermoluminescence, which involved heating flints found in the same mineral deposits. The age of those flints was determined to be roughly 300,000 years old, suggesting that our species emerged 100,000 years earlier than previously believed.

Modern facial morphology likely emerged early in our history

As part of their research, Hublin’s team set out to reconstruct a skull using various fossils from different specimens found at the site, the Post explained. They used a face and braincase found in 1961, a second brain case found in 1962, and a partial face discovered in 2007. The result was described as a skull with a small face shaped similar to those found in modern humans.

“Our findings suggest that modern human facial morphology was established early on in the history of our species, and that brain shape, and possibly brain function, evolved within the Homo sapiens lineage,” study co-author Philipp Gunz, also from the Max Planck Institute for Evolutionary Anthropology, said in a statement.

Frank Brown, a University of Utah geologist and author of the Kibish reanalysis who was not involved in the new research, said that the conclusion of the new study makes sense in light of the “near-but-not-quite modernity” of the Jebel Irhoud remains. “They're not Homo neanderthalensis. They're not Homo erectus. They're not Homo anybody else,” he told the Post, adding that they are not quite modern humans either. “The authors were careful to say that the remains are on their way to being anatomically modern.”

Furthermore, the fossils were discovered with stone tools and animal bones that appear to have been hunted, the researchers said in a statement. The stone tools linked to those remains appear to belong to the Middle Stone Age, and many of them were created from high-quality flint that appeared to have been brought to the site from other locations. Such tools likely helped nearly-modern humans spread throughout the continent of Africa, the authors noted.

“The stone artifacts from Jebel Irhoud look very similar to ones from deposits of similar age in east Africa and in southern Africa” Max Planck Institute archaeologist Shannon McPherron said. “It is likely that the technological innovations of the Middle Stone Age in Africa are linked to the emergence of Homo sapiens.”

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